package com.heima.kafka.sample;

import org.apache.kafka.clients.consumer.*;
import org.apache.kafka.clients.producer.ProducerConfig;
import org.apache.kafka.common.TopicPartition;

import java.time.Duration;
import java.util.Collections;
import java.util.Map;
import java.util.Properties;

/**
 * 消费者
 */
public class ConsumerQuickStart {
    public static void main(String[] args) {
        // 1. kafka的配置信息
        Properties prop = new Properties();
        // 1.1 链接地址
        prop.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "192.168.174.133:9092");
        // 1.2 key和value的反序列化器
        prop.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
        prop.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
        // 1.3 设置消费者组
        prop.put(ConsumerConfig.GROUP_ID_CONFIG, "group1");

        // 1.4 手动提交偏移量
        prop.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, false);

        // 2. 创建消费者对象
        KafkaConsumer<String, String> consumer = new KafkaConsumer<>(prop);
        // 3. 订阅主题
        consumer.subscribe(Collections.singleton("itcast-topic-out"));

        // 同步异步提交
        try {
            while(true) {
                ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(1000));
                for (ConsumerRecord<String, String> record : records) {
                    System.out.println(record.key());
                    System.out.println(record.value());
                    System.out.println(record.partition());
                    System.out.println(record.offset());
                }
                // 异步提交偏移量
                consumer.commitAsync();
            }
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("记录错误的信息:"+e);
        }finally {
            // 同步
            consumer.commitSync();
        }

        // 4. 拉取信息
        // while(true) {
        //     ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(1000));
        //     for (ConsumerRecord<String, String> record : records) {
        //         System.out.println(record.key());
        //         System.out.println(record.value());
        //         System.out.println(record.partition());
        //         System.out.println(record.offset());
        //     }
        //
        //     // 同步提交偏移量
        //     consumer.commitSync();
        //
        //     // 异步提交偏移量
        //     consumer.commitAsync(new OffsetCommitCallback(){
        //         @Override
        //         public void onComplete(Map<TopicPartition, OffsetAndMetadata> map, Exception e) {
        //             if(e!=null){
        //                 System.out.println("记录错误的提交偏移量"+map+", 异常信息为"+e);
        //             }
        //         }
        //     });
        // }
    }
}
